Vitess is a database clustering system designed to horizontally scale MySQL databases. CVE-2026-27969 is a path traversal vulnerability classified under CWE-22 that affects Vitess versions prior to 22.0.4 and between 23.0.0 and 23.0.3. The vulnerability occurs because Vitess does not properly restrict the pathname of files listed in backup manifest files during the restore process. An attacker who has read/write access to the backup storage location, such as an S3 bucket used for backups, can manipulate these manifest files to include paths that traverse directories outside the intended backup restore directory. Consequently, during restoration, files can be written to arbitrary locations accessible by the Vitess process. This can lead to unauthorized file writes in the production environment, potentially allowing attackers to access sensitive information or execute arbitrary commands with the privileges of the Vitess service. The vulnerability does not require user interaction and can be exploited remotely if the attacker has sufficient access to the backup storage. The issue is mitigated in Vitess versions 22.0.4 and 23.0.3, which include patches to properly validate and restrict file paths during restore. No known workarounds exist, making patching the only effective remediation. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges required beyond read/write access to backup storage, no user interaction, and high impact on confidentiality and integrity, with limited availability impact. No known exploits have been reported in the wild as of the publication date.

The impact of this vulnerability is significant for organizations using Vitess for MySQL clustering, especially those relying on cloud storage solutions like S3 for backups. An attacker with access to the backup storage can leverage this flaw to write malicious files into the production environment, potentially leading to unauthorized data access, data corruption, or remote code execution. This compromises the confidentiality, integrity, and availability of the database environment. Given Vitess's role in managing critical database infrastructure, exploitation could disrupt business operations, lead to data breaches, and facilitate lateral movement within the network. The vulnerability's ease of exploitation and high privileges gained make it a critical risk, particularly for organizations with insufficient access controls on backup storage. The lack of workarounds increases urgency for patching. Industries with high reliance on Vitess, such as cloud service providers, SaaS companies, and enterprises with large-scale MySQL deployments, are at elevated risk.

The primary mitigation is to upgrade Vitess to versions 22.0.4 or 23.0.3 or later, which contain patches that properly validate and restrict file paths during backup restore operations. Organizations should immediately audit and restrict access permissions to backup storage locations, ensuring that only trusted and minimal necessary entities have read/write access. Implement strict IAM policies for cloud storage buckets (e.g., S3) to prevent unauthorized modification of backup manifests. Additionally, monitor backup storage for unusual file changes or additions that could indicate tampering. Employ integrity verification mechanisms for backup manifests before restoration. Consider isolating backup restoration environments from production systems to limit potential damage from malicious restores. Regularly review and update incident response plans to address potential exploitation scenarios involving backup manipulation. Finally, maintain vigilance for any emerging exploit reports and apply security advisories promptly.